We're into a daily melt-freeze cycle. Be alert to changing snow conditions as the snow warms up.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
WEDNESDAY: Increasing cloud with light snow/rain in the evening, strong southwest wind, freezing level climbing to 2000 m after an overnight refreeze.THURSDAY: Mostly cloudy with light amounts of snow/rain, moderate southwest wind, freezing level up to 2200 m with little overnight refreeze.FRIDAY: Mostly cloudy with about 5 cm of wet snow later in the day, moderate southwest wind, freezing level holding at 2200 m.
Avalanche Summary
On Tuesday, several natural loose wet avalanches were observed in steep south-facing terrain (size 1). Increasing cloud cover will decrease the likelihood loose wet avalanches on Wednesday, but storm slabs and cornices remain a concern at higher elevations.
Snowpack Summary
The snowpack has entered a daily melt-freeze cycle. Hard crusts form overnight and become moist surface snow during the heat of the day. The exception is north-facing alpine terrain, where dry snow and isolated wind slabs may exist. The December facets and November rain crust are buried deep, but have not been reactive for a few weeks.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.